Carbon black process using flow reversal

ABSTRACT

A method of producing carbon black and a carbon black furnace are disclosed, the method involving introduction of a hydrocarbon feed axially into a reactor along the walls of which there has been established, by introduction of a fuel and oxygen, a mass of hot combustion gases and recovery of the carbon black from both ends of the reactor.

United States Patent 1191 Vanderveen Feb. 11, 1975 [54] CARBON BLACKPROCESS USING FLOW 3,072,695 2/1963 Clalassen et al. 423/455 3,23 ,3342/1966 He mers 423/456 REVERSAL 3,595,622 7/l97l Johnson 23/2595 [75]Inventor: Jo n nd r e Bartlesvrlle. 3,690,831 9/1972 Kobayashi et al.423/456 Okla. 3,728,437 4/1973 Vanderveen 423/450 ,7 ,5 2 l l 74 H I] l.42 445 [73] Assignee: Phillips Petroleum Company, 3 87 6 l 9 6 er et a3/ Bartlesvme Okla' Primary Examiner-Oscar R. Vladiz [22] Filed: Dec. 8,1972 Assistant ExaminerGary P. Straub [21] Appl. No.: 313,538

[57] ABSTRACT [52] Us Cl 423/456 23/259 5 423/450 A method of producingcarbon black and a carbon [51] 31/02 H5O black furnace are disclosed,the method involving in- [58] Fieid 423/450 3 456 457 troduction of ahydrocarbon feed axially into a reactor 23/259 along the walls of whichthere has been established, by

introduction of a fuel and oxygen, a mass of hot com- [56] ReferencesCited bustion gases and recovery of the carbon black from UNITED STATESPATENTS both ends of the reactor. 2,656,254 10/1953 Heller 423/456 6Claims 4 Drawing Figures 2O l5 l0 [IO /2O ,5 5 0 WA 6 d LL d WA 2 1 2 mN 1 r A Tm m Q W A Q ":1 0 :1 W62 Q \4 PATENTED FEB 1 1 1975 1 CARBONBLACK PROCESS USING FLOW REVERSAL This invention relates to a carbonblock process and to apparatus for carrying out the process.

In one of its more specific aspects, this invention relates to theproduction of furnace-oxidized black.

The production of furnace carbon blacks is well known. Such processesinvolve introducing a make-oil or hydrocarbon feed into a carbon blackreactor and into contact with hot combustion gases produced by theoxidation of a fuel with an oxidant, usually natural gas and air. Thecontact between the feed and the hot combustion gases raises the feed toits decomposition temperature at which temperature the feed decomposesto produce carbon black which is recovered from the furnace. The presentinvention involves a method of producing carbon black under the samegeneral principles and conditions, including aspects such as air to fuelratio, feeds, fuels and oxidants, as are generally employed to producecarbon black as illustrated, for example, in such US. Pat. Nos. as3,410,660 and 3,235,334, the disclosures of which are included herein byreference. The invention also involves apparatus for the production ofthe black.

The method of the present invention involves two embodiments. In thefirst, the hydrocarbon feed and air are introduced axially through oneend of the reactor and only air, or a vaporous oxidant, is introducedaxially through the other end. A-vaporous oxidant, preferably air oroxygen-enriched air, is added tangentially through the circumferentialperiphery of the reactor, being introduced at a plurality of pointsalong the longitudinal axis of the reactor. Fuel, preferably naturalgas, is added through the periphery of the reactor at a single locusabout mid-point along the length of the reactor. Introduction of thefuel in this manner produces hot combustion gases and oxidant as acylinder of flame into which the hydrocarbon feed is introduced. Thesmoke which is produced, and in which the carbon black is contained, isremoved and at least a portion of this smoke is passed into contact withthe hot combustion gases and vaporous oxidant to oxidize the black andblack is then recovered from the reactor proximate the hydrocarbon feedinlet or from both ends of the reactor proximate the locus ofintroduction of the hydrocarbon feed.

In a second embodiment of the invention, the hydrocarbon feed andvaporous oxidant are introduced axially through both ends of thereactor. The oxidant and fuel are introduced as described in the firstembodiment and a portion of the smoke is removed from both ends of thereactor proximate the locus of introduction of the hydrocarbon feed.

As mentioned, the method of the present invention employs hydrocarbonfeeds, air to hydrocarbon feed ratios in relation to air to fuel ratios,reaction temperatures and other operating conditions as are employed inthe prior art. In the present invention, inasmuch as the carbon blackproduct is passed in a direction opposite to the direction of thehydrocarbon feed introduction and through oxygen-containing gases underconditions to oxidize the black, it is important that these hotcombustion gases contain a sufficient quantity of oxygen to affect thatoxidation. Generally, air or an oxygen-containing gas is employed in aquantity sufficient to provide from about 1 to about 1.5 times thestoichiometric amount of oxygen required to oxidize the fuel.

To produce conventional carbon black of DPG below about 10, the excessair over that needed stoichiometrically for the fuel is between about300 to 1,000 SCF/gallon of feed. To produce oxidized carbon black of DPGgreater than about 10, the excess air will be about 1,000 to 6,000SCF/gallon of feed.

The method of this invention will be more readily understood ifexplained in conjunction with the attached drawings in which FIG. 1 is aview of a typical embodiment of the reactor, in elevation;

FIG. 2 is a crosssectional view through section 22 of FIG. 1;

FIG. 3 is one embodiment of the ends of the reactor; and,

FIG. 4 is a second embodiment of the ends of the reactor.

Referring now to FIG. 1, there is shown the internal configuration ofreactor 40, the insulation thereof being omitted, adapted withhydrocarbon feed inlet conduit 1 and oxidant or air inlet conduit 2entering the reactor at end 3. The opposite end 4 of the reactor issimilarly adapted with make-oil inlet conduit 1 and oxidant or air inletconduit 2.

In both instances, these inlet conduits penetrate through refractorywalls 6 which are preferably formed of refractory material and whichhave formed through them passages 20, these refractory walls beingpreferentially positioned in spaced relation to the ends of reactor toform sections 30 and 50 therebetween. However, walls 6 can be positionedcontiguous with the ends of the reactor and sections 30 and 50 can beeliminated. As shown in FIG. 2, passageways 20 can take the form of aplurality of passageways or a single passageway can be constructed inthe form of an annulus.

Sections 30 and 50' are adapted with conduit means 5 opening therefromeither radially or tangentially as smoke outlets.

Opening through the wall of the reactor circumferentially at a locusabout mid-point between the ends of the reactor along its longitudinalaxis are one or more vaporous fuel inlet conduits 15 which can be openat their inner ends or which can be adapted with a plurality ofapertures so as to discharge vaporous fuel in a plurality of streams.

Positioned along the longitudinal axis of the reactor and openingthereinto are a plurality of gaseous oxidant, or air inlet means 10 forthe introduction of an oxidant into the reactor. These can also belocated circumferentially and open through the reactor wall on a commondiameter.

As shown in FIG. 2, these air inlet conduits 10 will be adapted for thetangential introduction of the oxidant into the reactor to establish ahelically-moving layer of oxidant adjacent the inner wall of thereactor.

As shown in FIGS. 3 and 4, various adaptations of the axial hydrocarbonfeed inlet conduit means and oxidant inlet conduit means through the endrefractory walls, as well as the smoke outlet conduit means, arepossible. Inasmuch as the smoke will be at its usual elevatedtemperature of about 2,700F, it may be desirable to position a coolingjacket 9 in contact with the inlet conduits to maintain them at anoperable working temperature, a cooling medium, such as water, beingcirculated through the jacket through conduit means not shown.

The reactor and process can be operated with hydrocarbon feedintroduction into the reactor being made axially into one end or bothends of the reactor.

In that embodiment in which the hydrocarbon feed and air are introducedinto but one end of the reactor, air is introduced into the opposite endof the reactor. Fuel, preferably natural gas, is introduced centrallyalong the longitudinal axis of the reactor with air being introducedthrough the spaced-apart ports positioned along the longitudinal axis ofthe reactor.

The fuel gas is ignited and forms hot combustion gases upon oxidationwith air. These hot combustion gases are established as a cylinder offlame along the walls of the reactor. The hydrocarbon feed is brought toconventional decomposition temperatures by contact with the hotcombustion gases to form carbon black. This carbon black and the hotcombustion gases, in the form of smoke, pass from both ends of thereactor to subsequent quenching and recovery facilities.

In another embodiment, hydrocarbon feed and air are introduced in aboutlike amounts into both ends of the reactor and the smoke is removed fromboth ends of the reactor.

The reactor of this invention can be of any size. One suitable reactorhad an internal diameter of 5V2 inches, a length of inches betweeninsulation walls 6; the passages through the refractory walls wereA-inch diameter with eight passages being supplied through eachrefractory wall. This method of operation established a cylinder offlame having a diameter of about 2% inches.

For reactors of larger capacities, the reactor could have an internaldiameter of from about 5 /2 inches to about 20 inches, a length of fromabout 8 inches to about 16 inches between refractory walls, from four to16 passages through the insulation walls, these passageways being fromAr-inch to 2 inches in diameter.

The first-described reactor having a 5 /2 inch diameter was employedusing benzene as the hydrocarbon feed under the following conditions toproduce carbon black of the quality indicated below, the benzene beingintroduced into both ends of the reactor in about equal quantities.Rates shown are for each end of the reactor.

Operating Conditions For Each End of Reactor Benzene Feed Rate, gaL/hr.0.417 Axial Air, SCF/gal. lOO Tangential Air, SCF/hr. 720 Fuel Gas,SCF/hr. (CH 32 Reactor Temperature, F Reactor Pressure, inches,

water gage About 2700 1 Product Quality Mixture from Reactor NitrogenSurface Area, mlgm 39 lodine No mg/gm 44 DPG Adsorption. meq/gm 7 CTAB,mlgm DBP 24M4 Structure, cc/lOO gm 6O Photelometer 95 Yield, No. C/gal.benzene 3.0

'Cetyltrimethylammonium bromide "US, 3,548,454, Phillips PetroleumCompany (dibutylphthalate) extent of 30-50 DPG, such as are producedemploying nitric acid after-treatment. This is shown by the followingrun made at high tangential air rates, hydrocarbon feed and air, only,being introduced into each end of the reactor.

Operating Conditions For Each End of Reactor Benzene Feed Rate, gal/hr.0.15 Axial Air. SCF/gal. Tangential Air, SCF/hr. 960 Fuel Gas, SCF/hr.(CH.,) 40

Reactor Temperature, "F

About 2700 Reactor Pressure, psig Ol While the surface area of the blackof the second run was not as low as that of the black of the first run,the lower iodine number indicates the presence of oxygen groups on theblack to the extent that the diphenylguanidine test value of 31.5 waswithin the range of that for blacks which have been after treated withnitric acid.

This oxidative after-treating of the black seemingly occurs due tocontact of the black with the excess tangential air introduced along thelongitudinal axis of the reactor as the black moves from the centralportion of the reactor to either end in order to leave the reactor.

It will be evident that various modifications can be made to the methodand apparatus of this invention. Such, however, are considered as beingwithin the scope of the invention.

What is claimed is:

l. A method of producing carbon black in a reactor having two ends andbeing longitudinally disposed which comprises:

a. introducing a liquid hydrocarbon feed and a first gaseous oxidantselected from the group consisting of oxygen, oxygen-enriched air andair axially into an end of said reactor along its longitudinal axis;

b. introducing a second gaseous oxidant selected from the groupconsisting of oxygen, oxygenenriched air and airtangentially into saidreactor at a plurality of spaced apart loci along the longitudinal axisof said reactor;

0. introducing a gaseous hydrocarbon fuel into said reactorlongitudinally apart from the introduction of said liquid hydrocarbonfeed;

d. oxidizing said fuel with said second oxidant to produce hotcombustion gases containing said second gaseous oxidant positionedadjacent the walls of said reactor;

e. contacting said hydrocarbon feed with said hot combustion gases topyrolytically decompose said hydrocarbon feed to form carbon black;

f. passing said carbon black in a direction opposite to the direction ofhydrocarbon feed within said reactor into contact with said hotcombustion gases and second gaseous oxidant to oxidize said black; and,

g. recovering the carbon black produced from said reactor proximate thepoint of axial introduction of said hydrocarbon feed into said reactor.

2. The method of claim 1 in which said hydrocarbon feed and said firstgaseous oxidant are introduced into said reactor at both ends of saidreactor in about like amounts and carbon black is recovered from each ofthe respective ends of said reactor proximate to where the hydrocarbonfeed was introduced out of which said carbon black was formed.

3. The method of claim 2 in which said gaseous fuel is introduced intosaid reactor at a locus approximately equidistant between the oppositeends of said reactor.

4. The method of claim 3 in which said gaseous fuel is introduced intosaid reactor at a plurality of loci circumferentially positioned aroundsaid reactor on a common diameter.

5. The method of claim 3 in which said hot combustion gases areestablished as a cylinder of flame adjacent the walls of the reactor byintroducing a gaseous oxidant selected from the group consisting ofoxygen, oxygen-enriched air, and air tangentially into said reactor at aplurality of spaced apart loci along the longitudinal axis of saidreactor to establish a helically moving layer of oxidant adjacent theinner wall of said reactor, introducing a gaseous fuel into said reactorapproximately equidistant between the ends of said reactor, and ignitingthe gaseous fuel.

6. A method in accordance with claim 1 in which said hydrocarbon feedand said first gaseous oxidant are introduced axially into one end ofsaid reactor along its longitudinal axis and in which only a thirdgaseous oxidant selected from the group consisting of oxygen,oxygen-enriched air, and air is introduced axially through the other endof said reactor and in which carbon black is recovered from both ends ofsaid reactor.

1. A METHOD OF PRODUCING CARBON BLACK IN A REACTOR HAVING TWO ENDS ANDBEING LONGITUDINALLY DISPOSED WHICH COMPRISES: A INTRODUCING A LIQUIDHYDROCARBON FEED AND A FIRST GASEOUS OXIDANT SELECTED FROM THE GROUPCONSISTING OF OXYGEN, OXYGENENRICHED AIR AND AIR AXIALLY INTO AN END OFSAID REACTOR ALONG ITS LONGITUDINAL AXIS; B. INTRODUCING A SECONDGASEOUS OXIDANT SELECTED FROM THE GROUP CONSISTING OF OXYGEN,OXYGEN-ENRICHED AIR AND AIR TANGENTIALLY INTO SAID REACTOR AT APLURALITY OF SPACED APART LOCI ALONG THE LONGITUDINAL AXIS OF SAIDREACTOR; C. INTRODUCING A GASEOUS HYDROCARBON FUEL INTO SAID REACTORLONGITUDINALLY APART FROM THE INTRODUCTION OF SAID LIQUID HYDROCARBONFEED; D. OXIDING SAID FUEL WITH SAID SECOND OXIDANT TO PRODUCE HOTCOMBUSTION GASES CONTAINING SAID SECOND GASEOUS OXIDANT POSITIONEDADJACENT THE WALLS OF SAID REACTOR E. CONTACTING SAID HYDROCARBON FEEDWITH SAID HOT COMBUSTION GASES TO PYROLYTICALLY DECOMPOSE SAIDHYDROCARBON FEED TO FORM CARBON BLACK; F. PASSING SAID CARBON BLACK IN ADIRECTION OPPOSITE TO THE DIRECTION OF HYDROCARBON FEED WITHIN SAIDREACTOR INTO CONTACT WITH SAID HOT COMBUSTION GASES AND SECOND GASEOUSOXIDANT TO OXIDIZE SAID BLACK; AND, G. RECOVERING THE CARBON BLACKPRODUCED FROM SAID REACTOR PROXIMATE THE POINT OF AXIAL INTRODUCTION OFSAID HYDROCARBON FEED INTO SAID REACTOR.
 2. The method of claim 1 inwhich said hydrocarbon feed and said first gaseous oxidant areintroduced into said reactor at both ends of said reactor in about likeamounts and carbon black is recovered from each of the respective endsof said reactor proximate to where the hydrocarbon feed was introducedout of which said carbon black was formed.
 3. The method of claim 2 inwhich said gaseous fuel is introduced into said reactor at a locusapproximately equidistant between the opposite ends of said reactor. 4.The method of claim 3 in which said gaseous fuel is introduced into saidreactor at a plurality of loci circumferentially positioned around saidreactor on a common diameter.
 5. The method of claim 3 in which said hotcombustion gases are established as a cylinder of flame adjacent thewalls of the reactor by introducing a gaseous oxidant selected from thegroup consisting of oxygen, oxygen-enriched air, and air tangentiallyinto said reactor at a plurality of spaced apart loci along thelongitudinal axis of said reactor to establish a helically moving layerof oxidant adjacent the inner wall of said reactor, introducing agaseous fuel into said reactor approximately equidistant between theends of said reactor, and igniting the gaseous fuel.
 6. A method inaccordance with claim 1 in which said hydrocarbon feed and said firstgaseous oxidant are introduced axially into one end of said reactoralong its longitudinal axis and in which only a third gaseous oxidantselected from the group consisting of oxygen, oxygen-enriched air, andair is introduced axially through the other end of said reactor and inwhich carbon black is recovered from both ends of said reactor.